1. Field of the Invention
This invention relates to a device for heated wedge pressure welding by drawing of separating seams of a composite plastic profiled hollow section.
2. Description of the Prior Art
When sealing off landfills, so-called drain walls made of foil sections are put together, which are closed off at their vertical ends with profiled sections. The profiled sections of adjacent foil sections can be pushed into each other in such a way that they form a plastic profiled hollow section. This plastic profiled hollow section is the weak point of the drain wall formed in this way because the separating seams between the profiled sections of the composite plastic profiled hollow section cause the drain wall to become permeable. Attempts have been made to seal this leaky place by filling the hollow chamber of the plastic profiled hollow section with epoxy resin. However, the epoxy resin does not combine with the plastic of the plastic profiled hollow section. As a result it is not possible to achieve an absolutely tight closure of the separating seams, particularly if the plastic profiled hollow section buried in the ground expands or contracts in the course of temperature changes.